Send an event to the page load metrics to track resource starting.

chrome/browser/page_load_metrics/observers/core_page_load_metrics_observer.cc

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/page_load_metrics/observers/core_page_load_metrics_observer.h"
 
 #include <stddef.h>
 #include <stdint.h>
 #include <utility>
 
@@ skipping 640 matching lines @@
       event.GetType() == blink::WebInputEvent::kGestureScrollBegin) {
     received_scroll_input_after_first_paint_ = true;
     if (now.is_null())
       now = base::TimeTicks::Now();
     PAGE_LOAD_HISTOGRAM(internal::kHistogramFirstScrollInputAfterFirstPaint,
                         now - first_paint_);
   }
 }
 
 void CorePageLoadMetricsObserver::OnLoadedResource(
-    const page_load_metrics::ExtraRequestInfo& extra_request_info) {
-  if (extra_request_info.was_cached) {
+    const page_load_metrics::ExtraRequestCompleteInfo&
+        extra_request_complete_info) {
+  if (extra_request_complete_info.was_cached) {
     ++num_cache_resources_;
-    cache_bytes_ += extra_request_info.raw_body_bytes;
+    cache_bytes_ += extra_request_complete_info.raw_body_bytes;
   } else {
     ++num_network_resources_;
-    network_bytes_ += extra_request_info.raw_body_bytes;
+    network_bytes_ += extra_request_complete_info.raw_body_bytes;
   }
 }
 
 void CorePageLoadMetricsObserver::RecordTimingHistograms(
     const page_load_metrics::PageLoadTiming& timing,
     const page_load_metrics::PageLoadExtraInfo& info) {
   // Log time to first foreground / time to first background. Log counts that we
   // started a relevant page load in the foreground / background.
   if (!info.started_in_foreground && info.first_foreground_time) {
     PAGE_LOAD_HISTOGRAM(internal::kHistogramFirstForeground,
@@ skipping 148 matching lines @@
   }
 
   // Log the eTLD+1 of sites that did not report first meaningful paint.
   if (timing.paint_timing.first_paint &&
       !timing.paint_timing.first_meaningful_paint) {
     rappor::SampleDomainAndRegistryFromGURL(
         rappor_service,
         internal::kRapporMetricsNameFirstMeaningfulPaintNotRecorded, info.url);
   }
 }